package com.example.springboot.controller;


import cn.hutool.poi.excel.ExcelUtil;
import cn.hutool.poi.excel.ExcelReader;
import cn.hutool.poi.excel.ExcelWriter;
import jakarta.annotation.Resource;
import jakarta.servlet.ServletOutputStream;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import java.net.URLEncoder;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import org.springframework.web.bind.annotation.*;
import java.io.InputStream;
import java.util.List;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.example.springboot.common.Result;
import org.springframework.web.multipart.MultipartFile;
import com.example.springboot.service.IUserService;
import com.example.springboot.entity.User;

    import org.springframework.web.bind.annotation.RestController;
/**
* <p>
    *  前端控制器
    * </p>
*
* @author 子凡
* @since 2024-05-19
*/

    @RestController
@RequestMapping("/user")
        public class UserController {

    @Resource
    private IUserService userService;

    @PostMapping
    public Result save(@RequestBody User user) {
    userService.save(user);
    return Result.success();
    }


    @PutMapping
    public Result update(@RequestBody User user) {
    userService.updateById(user);
    return Result.success();
    }

    @DeleteMapping("/{id}")
    public Result delete(@PathVariable Integer id) {
    userService.removeById(id);
    return Result.success();
    }

    @PostMapping("/del/batch")
    public Result deleteBatch(@RequestBody List
    <Integer> ids) {
        userService.removeByIds(ids);
        return Result.success();
    }

        @GetMapping
        public Result findAll() {
        return Result.success(userService.list());
        }

        @GetMapping("/{id}")
        public Result findOne(@PathVariable Integer id) {
        return Result.success(userService.getById(id));
        }

        @GetMapping("/page")
        public Result findPage(@RequestParam(defaultValue = "") String name,
        @RequestParam Integer pageNum,
        @RequestParam Integer pageSize) {
        QueryWrapper<User> queryWrapper = new QueryWrapper<User>().orderByDesc("id");
        queryWrapper.like(!"".equals(name), "name", name);
        return Result.success(userService.page(new Page<>(pageNum, pageSize), queryWrapper));
        }

        /**
        * 导出接口
        */
        @GetMapping("/export")
        public void export(HttpServletResponse response) throws Exception {
        // 从数据库查询出所有的数据
        List<User> list = userService.list();
        // 在内存操作，写出到浏览器
        ExcelWriter writer = ExcelUtil.getWriter(true);

        // 一次性写出list内的对象到excel，使用默认样式，强制输出标题
        writer.write(list, true);

        // 设置浏览器响应的格式
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=utf-8");
        String fileName = URLEncoder.encode("User信息表", "UTF-8");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xlsx");

        ServletOutputStream out = response.getOutputStream();
        writer.flush(out, true);
        out.close();
        writer.close();

        }

        /**
        * excel 导入
        * @param file
        * @throws Exception
        */
        @PostMapping("/import")
        public Result imp(MultipartFile file) throws Exception {
        InputStream inputStream = file.getInputStream();
        ExcelReader reader = ExcelUtil.getReader(inputStream);
        // 通过 javabean的方式读取Excel内的对象，但是要求表头必须是英文，跟javabean的属性要对应起来
        List<User> list = reader.readAll(User.class);

        userService.saveBatch(list);
        return Result.success();
        }

        }






